Answer:
-3.396 m/s or 3.465 m/s
Explanation:
v = Speed of sound in air = 343 m/s
= Relative speed of the singer
f = Observed frequency
f' = Actual frequency
1% change can mean 
From the Doppler effect equation we have
The velocity is -3.396 m/s
when 
The velocity is 3.465 m/s
Potential energy + kinetic energy = constant at every moment in time
At the highest point:
potential energy is at its maximum
kinetic energy is zero
I think its Coulomb's law<span>
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When the car comes to a stop, the final velocity must be 0 m/s.
Since the car js decelerating in a forward direction, acceleration must be negative.
final v = initial v + a•t
0 = 20 + (-6)t
t = 3.33s
